TABLE OF CONTENTS Pages Symposium 1 - the National Sea ...

The Effects of Ultraviolet Filtration on the
Production of the Gold Fish
Carassius auratus in Recirculating Systems
Donald I. Anadu Ph.D.
Department of Biological Sciences,
South Carolina State University, P.O. Box 7501. Orangeburg, SC 29117. U.S.A.
Abstract
Goldfish (Carassius auratus) were reared in two recirculating systems initially under the
same settings and UV conditions for period of 100 days. Halfway through the
experiment, the supply of the UV irradiation in one the setting was discontinued. Several
water quality parameters were monitored in both settings at the two different times. The
results indicate that UV systems enhanced the growth of the fish, significantly increased
the relative growth rate, the production, the survival and the yield of the fish population.
Specifically, the ratio of the relative growth rates for the UV to the non-UV treated
goldfish was 23:1., production 26:1., survival,1.8:1 and yield 2:1.The condition factors
for both populations were not significantly different at 0.9:1 ratio. These findings indicate
that there were positive correlation between UV irradiation and most goldfish production
parameters.
Introduction
As aquaculture becomes an important facet of world fish production, improved principles
and techniques involved in this practice will enhance the contribution of aquaculture to
the fisheries industry. The major goal of a successful aquaculture is to maximize
production and therefore profit.
Water in different fish production systems is at risk of contamination from waterborne
pathogenic organisms. These pathogens have undesirable effects on the main goal of a
successful aquaculture, which is to maximize production (profit) in the system.
Ultraviolet (UV) irradiation systems have been applied both as water and air clarifier and
sterilizers for the past 50 years. Their applications have included; the disinfecting of
recycled distilled water in pharmaceutical and cosmetic industries, kidney dialysis water,
frozen juice concentrate makeup water, beverage bottle and container rinse water, cottage
cheese wash water, in fish hatchery water supply, control of algae in open fish ponds,
control of bacteria in ornamental fish production and aquarium systems and in the control
of tuberculosis Kizer, (1990) as well as other airborne viruses, mold spores and
microorganisms.
The objectives of this study were i) To estimate gold fish production parameters in
experimental recirculating system without UV irradiation ii) To estimate gold fish
production parameters in experimental recirculating system with UV irradiation and iii)
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